I am doubtful whether hypnosis could help your memory in general. However, if there was some specific information that you needed to remember, there are techniques that one can use for improve memory. These are known as mnemonic devices (which just means memory techniques). One could apply these to many different things that one might want to remember. For example, incorporating the information into a rhyme, a song, or an easy to remember phrase or word are some techniques that can be used. You could look on Google for mnemonic devices, if you wanted. I am not familiar with a role for hypnosis in memory, however.